1. Field of the Invention
The subject invention relates to a heating, ventilating, and air conditioning assembly for a vehicle having an improved air mixing door.
2. Description of the Prior Art
Conventional heating, ventilating, and air conditioning (HVAC) assemblies include a housing having an inlet and a number of outlets. The outlets disperse a flow of air into various portions of a passenger compartment. An evaporator and a heater core are typically disposed downstream of the inlet and upstream of the outlets. The evaporator is designed to dehumidify and cool the air while the heater core is designed to heat the air. The housing can define a first quadrant, which receives the cooled air, a second quadrant, which receives the heated air, and a third quadrant, which can receive and blend both the cooled and heated air.
At least one air mixing door is typically mounted within the housing to control a flow of air throughout the various quadrants of the housing which transmits air of varied temperatures into the portions of the passenger compartment. The air mixing door often pivots between different positions to vary the temperature of the air flowing into the passenger compartment. The air mixing door also includes seals for seating against a full cooling seat and a full heating seat of the housing. Occasionally, when the air mixing door initially moves away from the full heating seats, a sudden rush of air passes over the air mixing door. This sudden rush of air creates an undesirable thermodynamic effect which is noticed by occupants within the passenger compartment.
Accordingly, it would be desirable to develop an air mixing door which significantly reduces and/or eliminates the sudden rush of air when the air mixing door moves from certain seated positions.
A heating, ventilating, and air conditioning (HVAC) assembly for heating, venting, and cooling a passenger compartment of a vehicle. The HVAC assembly comprises a housing having an inlet and at least one outlet for directing a flow of air into the passenger compartment. The housing defines first and second quadrants disposed between the inlet and outlet. At least one heat exchanger is disposed within the housing downstream of the inlet and upstream of the outlet. An air mixing door, having first and second sides, is mounted to the housing downstream of the inlet and upstream of the outlet. The air mixing door has a first position directing substantially all of the air through the first quadrant, a second position directing substantially all of the air through the second quadrant, and a third position, infinitely variable between the first and second positions which directs a flow of air through both of the first and second quadrants. A first seal is mounted to the first side of the air mixing door with the first seal seating against the housing when the air mixing door is in the first position. A second seal is mounted to the second side of the air mixing door with the second seal seating against the housing when the air mixing door is in the second position. A diffuser is mounted to at least one of the sides of the air mixing door. The diffuser has a plurality of passageways to interrupt a flow of air passing around the air mixing door when the air mixing door initially moves from one of the first and second positions to the third position, thereby controlling an initial flow of air into at least one of the quadrants.
Accordingly, the subject invention provides for a HVAC assembly having an air mixing door which includes a diffuser for significantly reducing and/or eliminating any sudden rush of air when the air mixing door moves from a full heat seated position.